1 /* Copyright (C) 2010-2016 The RetroArch team
2  *
3  * ---------------------------------------------------------------------------------------
4  * The following license statement only applies to this libretro API header (libretro.h).
5  * ---------------------------------------------------------------------------------------
6  *
7  * Permission is hereby granted, free of charge,
8  * to any person obtaining a copy of this software and associated documentation files (the "Software"),
9  * to deal in the Software without restriction, including without limitation the rights to
10  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
11  * and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
16  * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
19  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21  */
22 
23 #ifndef LIBRETRO_H__
24 #define LIBRETRO_H__
25 
26 #include <stdint.h>
27 #include <stddef.h>
28 #include <limits.h>
29 
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33 
34 #ifndef __cplusplus
35 #if defined(_MSC_VER) && !defined(SN_TARGET_PS3)
36 /* Hack applied for MSVC when compiling in C89 mode
37  * as it isn't C99-compliant. */
38 #define bool unsigned char
39 #define true 1
40 #define false 0
41 #else
42 #include <stdbool.h>
43 #endif
44 #endif
45 
46 #ifndef RETRO_CALLCONV
47 #  if defined(__GNUC__) && defined(__i386__) && !defined(__x86_64__)
48 #    define RETRO_CALLCONV __attribute__((cdecl))
49 #  elif defined(_MSC_VER) && defined(_M_X86) && !defined(_M_X64)
50 #    define RETRO_CALLCONV __cdecl
51 #  else
52 #    define RETRO_CALLCONV /* all other platforms only have one calling convention each */
53 #  endif
54 #endif
55 
56 #ifndef RETRO_API
57 #  if defined(_WIN32) || defined(__CYGWIN__) || defined(__MINGW32__)
58 #    ifdef RETRO_IMPORT_SYMBOLS
59 #      ifdef __GNUC__
60 #        define RETRO_API RETRO_CALLCONV __attribute__((__dllimport__))
61 #      else
62 #        define RETRO_API RETRO_CALLCONV __declspec(dllimport)
63 #      endif
64 #    else
65 #      ifdef __GNUC__
66 #        define RETRO_API RETRO_CALLCONV __attribute__((__dllexport__))
67 #      else
68 #        define RETRO_API RETRO_CALLCONV __declspec(dllexport)
69 #      endif
70 #    endif
71 #  else
72 #      if defined(__GNUC__) && __GNUC__ >= 4
73 #        define RETRO_API RETRO_CALLCONV __attribute__((__visibility__("default")))
74 #      else
75 #        define RETRO_API RETRO_CALLCONV
76 #      endif
77 #  endif
78 #endif
79 
80 /* Used for checking API/ABI mismatches that can break libretro
81  * implementations.
82  * It is not incremented for compatible changes to the API.
83  */
84 #define RETRO_API_VERSION         1
85 
86 /*
87  * Libretro's fundamental device abstractions.
88  *
89  * Libretro's input system consists of some standardized device types,
90  * such as a joypad (with/without analog), mouse, keyboard, lightgun
91  * and a pointer.
92  *
93  * The functionality of these devices are fixed, and individual cores
94  * map their own concept of a controller to libretro's abstractions.
95  * This makes it possible for frontends to map the abstract types to a
96  * real input device, and not having to worry about binding input
97  * correctly to arbitrary controller layouts.
98  */
99 
100 #define RETRO_DEVICE_TYPE_SHIFT         8
101 #define RETRO_DEVICE_MASK               ((1 << RETRO_DEVICE_TYPE_SHIFT) - 1)
102 #define RETRO_DEVICE_SUBCLASS(base, id) (((id + 1) << RETRO_DEVICE_TYPE_SHIFT) | base)
103 
104 /* Input disabled. */
105 #define RETRO_DEVICE_NONE         0
106 
107 /* The JOYPAD is called RetroPad. It is essentially a Super Nintendo
108  * controller, but with additional L2/R2/L3/R3 buttons, similar to a
109  * PS1 DualShock. */
110 #define RETRO_DEVICE_JOYPAD       1
111 
112 /* The mouse is a simple mouse, similar to Super Nintendo's mouse.
113  * X and Y coordinates are reported relatively to last poll (poll callback).
114  * It is up to the libretro implementation to keep track of where the mouse
115  * pointer is supposed to be on the screen.
116  * The frontend must make sure not to interfere with its own hardware
117  * mouse pointer.
118  */
119 #define RETRO_DEVICE_MOUSE        2
120 
121 /* KEYBOARD device lets one poll for raw key pressed.
122  * It is poll based, so input callback will return with the current
123  * pressed state.
124  * For event/text based keyboard input, see
125  * RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK.
126  */
127 #define RETRO_DEVICE_KEYBOARD     3
128 
129 /* Lightgun X/Y coordinates are reported relatively to last poll,
130  * similar to mouse. */
131 #define RETRO_DEVICE_LIGHTGUN     4
132 
133 /* The ANALOG device is an extension to JOYPAD (RetroPad).
134  * Similar to DualShock it adds two analog sticks.
135  * This is treated as a separate device type as it returns values in the
136  * full analog range of [-0x8000, 0x7fff]. Positive X axis is right.
137  * Positive Y axis is down.
138  * Only use ANALOG type when polling for analog values of the axes.
139  */
140 #define RETRO_DEVICE_ANALOG       5
141 
142 /* Abstracts the concept of a pointing mechanism, e.g. touch.
143  * This allows libretro to query in absolute coordinates where on the
144  * screen a mouse (or something similar) is being placed.
145  * For a touch centric device, coordinates reported are the coordinates
146  * of the press.
147  *
148  * Coordinates in X and Y are reported as:
149  * [-0x7fff, 0x7fff]: -0x7fff corresponds to the far left/top of the screen,
150  * and 0x7fff corresponds to the far right/bottom of the screen.
151  * The "screen" is here defined as area that is passed to the frontend and
152  * later displayed on the monitor.
153  *
154  * The frontend is free to scale/resize this screen as it sees fit, however,
155  * (X, Y) = (-0x7fff, -0x7fff) will correspond to the top-left pixel of the
156  * game image, etc.
157  *
158  * To check if the pointer coordinates are valid (e.g. a touch display
159  * actually being touched), PRESSED returns 1 or 0.
160  *
161  * If using a mouse on a desktop, PRESSED will usually correspond to the
162  * left mouse button, but this is a frontend decision.
163  * PRESSED will only return 1 if the pointer is inside the game screen.
164  *
165  * For multi-touch, the index variable can be used to successively query
166  * more presses.
167  * If index = 0 returns true for _PRESSED, coordinates can be extracted
168  * with _X, _Y for index = 0. One can then query _PRESSED, _X, _Y with
169  * index = 1, and so on.
170  * Eventually _PRESSED will return false for an index. No further presses
171  * are registered at this point. */
172 #define RETRO_DEVICE_POINTER      6
173 
174 /* Buttons for the RetroPad (JOYPAD).
175  * The placement of these is equivalent to placements on the
176  * Super Nintendo controller.
177  * L2/R2/L3/R3 buttons correspond to the PS1 DualShock. */
178 #define RETRO_DEVICE_ID_JOYPAD_B        0
179 #define RETRO_DEVICE_ID_JOYPAD_Y        1
180 #define RETRO_DEVICE_ID_JOYPAD_SELECT   2
181 #define RETRO_DEVICE_ID_JOYPAD_START    3
182 #define RETRO_DEVICE_ID_JOYPAD_UP       4
183 #define RETRO_DEVICE_ID_JOYPAD_DOWN     5
184 #define RETRO_DEVICE_ID_JOYPAD_LEFT     6
185 #define RETRO_DEVICE_ID_JOYPAD_RIGHT    7
186 #define RETRO_DEVICE_ID_JOYPAD_A        8
187 #define RETRO_DEVICE_ID_JOYPAD_X        9
188 #define RETRO_DEVICE_ID_JOYPAD_L       10
189 #define RETRO_DEVICE_ID_JOYPAD_R       11
190 #define RETRO_DEVICE_ID_JOYPAD_L2      12
191 #define RETRO_DEVICE_ID_JOYPAD_R2      13
192 #define RETRO_DEVICE_ID_JOYPAD_L3      14
193 #define RETRO_DEVICE_ID_JOYPAD_R3      15
194 
195 /* Index / Id values for ANALOG device. */
196 #define RETRO_DEVICE_INDEX_ANALOG_LEFT   0
197 #define RETRO_DEVICE_INDEX_ANALOG_RIGHT  1
198 #define RETRO_DEVICE_ID_ANALOG_X         0
199 #define RETRO_DEVICE_ID_ANALOG_Y         1
200 
201 /* Id values for MOUSE. */
202 #define RETRO_DEVICE_ID_MOUSE_X                0
203 #define RETRO_DEVICE_ID_MOUSE_Y                1
204 #define RETRO_DEVICE_ID_MOUSE_LEFT             2
205 #define RETRO_DEVICE_ID_MOUSE_RIGHT            3
206 #define RETRO_DEVICE_ID_MOUSE_WHEELUP          4
207 #define RETRO_DEVICE_ID_MOUSE_WHEELDOWN        5
208 #define RETRO_DEVICE_ID_MOUSE_MIDDLE           6
209 #define RETRO_DEVICE_ID_MOUSE_HORIZ_WHEELUP    7
210 #define RETRO_DEVICE_ID_MOUSE_HORIZ_WHEELDOWN  8
211 
212 /* Id values for LIGHTGUN types. */
213 #define RETRO_DEVICE_ID_LIGHTGUN_X        0
214 #define RETRO_DEVICE_ID_LIGHTGUN_Y        1
215 #define RETRO_DEVICE_ID_LIGHTGUN_TRIGGER  2
216 #define RETRO_DEVICE_ID_LIGHTGUN_CURSOR   3
217 #define RETRO_DEVICE_ID_LIGHTGUN_TURBO    4
218 #define RETRO_DEVICE_ID_LIGHTGUN_PAUSE    5
219 #define RETRO_DEVICE_ID_LIGHTGUN_START    6
220 
221 /* Id values for POINTER. */
222 #define RETRO_DEVICE_ID_POINTER_X         0
223 #define RETRO_DEVICE_ID_POINTER_Y         1
224 #define RETRO_DEVICE_ID_POINTER_PRESSED   2
225 
226 /* Returned from retro_get_region(). */
227 #define RETRO_REGION_NTSC  0
228 #define RETRO_REGION_PAL   1
229 
230 /* Id values for LANGUAGE */
231 enum retro_language
232 {
233    RETRO_LANGUAGE_ENGLISH             =  0,
234    RETRO_LANGUAGE_JAPANESE            =  1,
235    RETRO_LANGUAGE_FRENCH              =  2,
236    RETRO_LANGUAGE_SPANISH             =  3,
237    RETRO_LANGUAGE_GERMAN              =  4,
238    RETRO_LANGUAGE_ITALIAN             =  5,
239    RETRO_LANGUAGE_DUTCH               =  6,
240    RETRO_LANGUAGE_PORTUGUESE          =  7,
241    RETRO_LANGUAGE_RUSSIAN             =  8,
242    RETRO_LANGUAGE_KOREAN              =  9,
243    RETRO_LANGUAGE_CHINESE_TRADITIONAL = 10,
244    RETRO_LANGUAGE_CHINESE_SIMPLIFIED  = 11,
245    RETRO_LANGUAGE_ESPERANTO           = 12,
246    RETRO_LANGUAGE_POLISH              = 13,
247    RETRO_LANGUAGE_LAST,
248 
249    /* Ensure sizeof(enum) == sizeof(int) */
250    RETRO_LANGUAGE_DUMMY          = INT_MAX
251 };
252 
253 /* Passed to retro_get_memory_data/size().
254  * If the memory type doesn't apply to the
255  * implementation NULL/0 can be returned.
256  */
257 #define RETRO_MEMORY_MASK        0xff
258 
259 /* Regular save RAM. This RAM is usually found on a game cartridge,
260  * backed up by a battery.
261  * If save game data is too complex for a single memory buffer,
262  * the SAVE_DIRECTORY (preferably) or SYSTEM_DIRECTORY environment
263  * callback can be used. */
264 #define RETRO_MEMORY_SAVE_RAM    0
265 
266 /* Some games have a built-in clock to keep track of time.
267  * This memory is usually just a couple of bytes to keep track of time.
268  */
269 #define RETRO_MEMORY_RTC         1
270 
271 /* System ram lets a frontend peek into a game systems main RAM. */
272 #define RETRO_MEMORY_SYSTEM_RAM  2
273 
274 /* Video ram lets a frontend peek into a game systems video RAM (VRAM). */
275 #define RETRO_MEMORY_VIDEO_RAM   3
276 
277 /* Keysyms used for ID in input state callback when polling RETRO_KEYBOARD. */
278 enum retro_key
279 {
280    RETROK_UNKNOWN        = 0,
281    RETROK_FIRST          = 0,
282    RETROK_BACKSPACE      = 8,
283    RETROK_TAB            = 9,
284    RETROK_CLEAR          = 12,
285    RETROK_RETURN         = 13,
286    RETROK_PAUSE          = 19,
287    RETROK_ESCAPE         = 27,
288    RETROK_SPACE          = 32,
289    RETROK_EXCLAIM        = 33,
290    RETROK_QUOTEDBL       = 34,
291    RETROK_HASH           = 35,
292    RETROK_DOLLAR         = 36,
293    RETROK_AMPERSAND      = 38,
294    RETROK_QUOTE          = 39,
295    RETROK_LEFTPAREN      = 40,
296    RETROK_RIGHTPAREN     = 41,
297    RETROK_ASTERISK       = 42,
298    RETROK_PLUS           = 43,
299    RETROK_COMMA          = 44,
300    RETROK_MINUS          = 45,
301    RETROK_PERIOD         = 46,
302    RETROK_SLASH          = 47,
303    RETROK_0              = 48,
304    RETROK_1              = 49,
305    RETROK_2              = 50,
306    RETROK_3              = 51,
307    RETROK_4              = 52,
308    RETROK_5              = 53,
309    RETROK_6              = 54,
310    RETROK_7              = 55,
311    RETROK_8              = 56,
312    RETROK_9              = 57,
313    RETROK_COLON          = 58,
314    RETROK_SEMICOLON      = 59,
315    RETROK_LESS           = 60,
316    RETROK_EQUALS         = 61,
317    RETROK_GREATER        = 62,
318    RETROK_QUESTION       = 63,
319    RETROK_AT             = 64,
320    RETROK_LEFTBRACKET    = 91,
321    RETROK_BACKSLASH      = 92,
322    RETROK_RIGHTBRACKET   = 93,
323    RETROK_CARET          = 94,
324    RETROK_UNDERSCORE     = 95,
325    RETROK_BACKQUOTE      = 96,
326    RETROK_a              = 97,
327    RETROK_b              = 98,
328    RETROK_c              = 99,
329    RETROK_d              = 100,
330    RETROK_e              = 101,
331    RETROK_f              = 102,
332    RETROK_g              = 103,
333    RETROK_h              = 104,
334    RETROK_i              = 105,
335    RETROK_j              = 106,
336    RETROK_k              = 107,
337    RETROK_l              = 108,
338    RETROK_m              = 109,
339    RETROK_n              = 110,
340    RETROK_o              = 111,
341    RETROK_p              = 112,
342    RETROK_q              = 113,
343    RETROK_r              = 114,
344    RETROK_s              = 115,
345    RETROK_t              = 116,
346    RETROK_u              = 117,
347    RETROK_v              = 118,
348    RETROK_w              = 119,
349    RETROK_x              = 120,
350    RETROK_y              = 121,
351    RETROK_z              = 122,
352    RETROK_DELETE         = 127,
353 
354    RETROK_KP0            = 256,
355    RETROK_KP1            = 257,
356    RETROK_KP2            = 258,
357    RETROK_KP3            = 259,
358    RETROK_KP4            = 260,
359    RETROK_KP5            = 261,
360    RETROK_KP6            = 262,
361    RETROK_KP7            = 263,
362    RETROK_KP8            = 264,
363    RETROK_KP9            = 265,
364    RETROK_KP_PERIOD      = 266,
365    RETROK_KP_DIVIDE      = 267,
366    RETROK_KP_MULTIPLY    = 268,
367    RETROK_KP_MINUS       = 269,
368    RETROK_KP_PLUS        = 270,
369    RETROK_KP_ENTER       = 271,
370    RETROK_KP_EQUALS      = 272,
371 
372    RETROK_UP             = 273,
373    RETROK_DOWN           = 274,
374    RETROK_RIGHT          = 275,
375    RETROK_LEFT           = 276,
376    RETROK_INSERT         = 277,
377    RETROK_HOME           = 278,
378    RETROK_END            = 279,
379    RETROK_PAGEUP         = 280,
380    RETROK_PAGEDOWN       = 281,
381 
382    RETROK_F1             = 282,
383    RETROK_F2             = 283,
384    RETROK_F3             = 284,
385    RETROK_F4             = 285,
386    RETROK_F5             = 286,
387    RETROK_F6             = 287,
388    RETROK_F7             = 288,
389    RETROK_F8             = 289,
390    RETROK_F9             = 290,
391    RETROK_F10            = 291,
392    RETROK_F11            = 292,
393    RETROK_F12            = 293,
394    RETROK_F13            = 294,
395    RETROK_F14            = 295,
396    RETROK_F15            = 296,
397 
398    RETROK_NUMLOCK        = 300,
399    RETROK_CAPSLOCK       = 301,
400    RETROK_SCROLLOCK      = 302,
401    RETROK_RSHIFT         = 303,
402    RETROK_LSHIFT         = 304,
403    RETROK_RCTRL          = 305,
404    RETROK_LCTRL          = 306,
405    RETROK_RALT           = 307,
406    RETROK_LALT           = 308,
407    RETROK_RMETA          = 309,
408    RETROK_LMETA          = 310,
409    RETROK_LSUPER         = 311,
410    RETROK_RSUPER         = 312,
411    RETROK_MODE           = 313,
412    RETROK_COMPOSE        = 314,
413 
414    RETROK_HELP           = 315,
415    RETROK_PRINT          = 316,
416    RETROK_SYSREQ         = 317,
417    RETROK_BREAK          = 318,
418    RETROK_MENU           = 319,
419    RETROK_POWER          = 320,
420    RETROK_EURO           = 321,
421    RETROK_UNDO           = 322,
422 
423    RETROK_LAST,
424 
425    RETROK_DUMMY          = INT_MAX /* Ensure sizeof(enum) == sizeof(int) */
426 };
427 
428 enum retro_mod
429 {
430    RETROKMOD_NONE       = 0x0000,
431 
432    RETROKMOD_SHIFT      = 0x01,
433    RETROKMOD_CTRL       = 0x02,
434    RETROKMOD_ALT        = 0x04,
435    RETROKMOD_META       = 0x08,
436 
437    RETROKMOD_NUMLOCK    = 0x10,
438    RETROKMOD_CAPSLOCK   = 0x20,
439    RETROKMOD_SCROLLOCK  = 0x40,
440 
441    RETROKMOD_DUMMY = INT_MAX /* Ensure sizeof(enum) == sizeof(int) */
442 };
443 
444 /* If set, this call is not part of the public libretro API yet. It can
445  * change or be removed at any time. */
446 #define RETRO_ENVIRONMENT_EXPERIMENTAL 0x10000
447 /* Environment callback to be used internally in frontend. */
448 #define RETRO_ENVIRONMENT_PRIVATE 0x20000
449 
450 /* Environment commands. */
451 #define RETRO_ENVIRONMENT_SET_ROTATION  1  /* const unsigned * --
452                                             * Sets screen rotation of graphics.
453                                             * Is only implemented if rotation can be accelerated by hardware.
454                                             * Valid values are 0, 1, 2, 3, which rotates screen by 0, 90, 180,
455                                             * 270 degrees counter-clockwise respectively.
456                                             */
457 #define RETRO_ENVIRONMENT_GET_OVERSCAN  2  /* bool * --
458                                             * Boolean value whether or not the implementation should use overscan,
459                                             * or crop away overscan.
460                                             */
461 #define RETRO_ENVIRONMENT_GET_CAN_DUPE  3  /* bool * --
462                                             * Boolean value whether or not frontend supports frame duping,
463                                             * passing NULL to video frame callback.
464                                             */
465 
466                                            /* Environ 4, 5 are no longer supported (GET_VARIABLE / SET_VARIABLES),
467                                             * and reserved to avoid possible ABI clash.
468                                             */
469 
470 #define RETRO_ENVIRONMENT_SET_MESSAGE   6  /* const struct retro_message * --
471                                             * Sets a message to be displayed in implementation-specific manner
472                                             * for a certain amount of 'frames'.
473                                             * Should not be used for trivial messages, which should simply be
474                                             * logged via RETRO_ENVIRONMENT_GET_LOG_INTERFACE (or as a
475                                             * fallback, stderr).
476                                             */
477 #define RETRO_ENVIRONMENT_SHUTDOWN      7  /* N/A (NULL) --
478                                             * Requests the frontend to shutdown.
479                                             * Should only be used if game has a specific
480                                             * way to shutdown the game from a menu item or similar.
481                                             */
482 #define RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL 8
483                                            /* const unsigned * --
484                                             * Gives a hint to the frontend how demanding this implementation
485                                             * is on a system. E.g. reporting a level of 2 means
486                                             * this implementation should run decently on all frontends
487                                             * of level 2 and up.
488                                             *
489                                             * It can be used by the frontend to potentially warn
490                                             * about too demanding implementations.
491                                             *
492                                             * The levels are "floating".
493                                             *
494                                             * This function can be called on a per-game basis,
495                                             * as certain games an implementation can play might be
496                                             * particularly demanding.
497                                             * If called, it should be called in retro_load_game().
498                                             */
499 #define RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY 9
500                                            /* const char ** --
501                                             * Returns the "system" directory of the frontend.
502                                             * This directory can be used to store system specific
503                                             * content such as BIOSes, configuration data, etc.
504                                             * The returned value can be NULL.
505                                             * If so, no such directory is defined,
506                                             * and it's up to the implementation to find a suitable directory.
507                                             *
508                                             * NOTE: Some cores used this folder also for "save" data such as
509                                             * memory cards, etc, for lack of a better place to put it.
510                                             * This is now discouraged, and if possible, cores should try to
511                                             * use the new GET_SAVE_DIRECTORY.
512                                             */
513 #define RETRO_ENVIRONMENT_SET_PIXEL_FORMAT 10
514                                            /* const enum retro_pixel_format * --
515                                             * Sets the internal pixel format used by the implementation.
516                                             * The default pixel format is RETRO_PIXEL_FORMAT_0RGB1555.
517                                             * This pixel format however, is deprecated (see enum retro_pixel_format).
518                                             * If the call returns false, the frontend does not support this pixel
519                                             * format.
520                                             *
521                                             * This function should be called inside retro_load_game() or
522                                             * retro_get_system_av_info().
523                                             */
524 #define RETRO_ENVIRONMENT_SET_INPUT_DESCRIPTORS 11
525                                            /* const struct retro_input_descriptor * --
526                                             * Sets an array of retro_input_descriptors.
527                                             * It is up to the frontend to present this in a usable way.
528                                             * The array is terminated by retro_input_descriptor::description
529                                             * being set to NULL.
530                                             * This function can be called at any time, but it is recommended
531                                             * to call it as early as possible.
532                                             */
533 #define RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK 12
534                                            /* const struct retro_keyboard_callback * --
535                                             * Sets a callback function used to notify core about keyboard events.
536                                             */
537 #define RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE 13
538                                            /* const struct retro_disk_control_callback * --
539                                             * Sets an interface which frontend can use to eject and insert
540                                             * disk images.
541                                             * This is used for games which consist of multiple images and
542                                             * must be manually swapped out by the user (e.g. PSX).
543                                             */
544 #define RETRO_ENVIRONMENT_SET_HW_RENDER 14
545                                            /* struct retro_hw_render_callback * --
546                                             * Sets an interface to let a libretro core render with
547                                             * hardware acceleration.
548                                             * Should be called in retro_load_game().
549                                             * If successful, libretro cores will be able to render to a
550                                             * frontend-provided framebuffer.
551                                             * The size of this framebuffer will be at least as large as
552                                             * max_width/max_height provided in get_av_info().
553                                             * If HW rendering is used, pass only RETRO_HW_FRAME_BUFFER_VALID or
554                                             * NULL to retro_video_refresh_t.
555                                             */
556 #define RETRO_ENVIRONMENT_GET_VARIABLE 15
557                                            /* struct retro_variable * --
558                                             * Interface to acquire user-defined information from environment
559                                             * that cannot feasibly be supported in a multi-system way.
560                                             * 'key' should be set to a key which has already been set by
561                                             * SET_VARIABLES.
562                                             * 'data' will be set to a value or NULL.
563                                             */
564 #define RETRO_ENVIRONMENT_SET_VARIABLES 16
565                                            /* const struct retro_variable * --
566                                             * Allows an implementation to signal the environment
567                                             * which variables it might want to check for later using
568                                             * GET_VARIABLE.
569                                             * This allows the frontend to present these variables to
570                                             * a user dynamically.
571                                             * This should be called as early as possible (ideally in
572                                             * retro_set_environment).
573                                             *
574                                             * 'data' points to an array of retro_variable structs
575                                             * terminated by a { NULL, NULL } element.
576                                             * retro_variable::key should be namespaced to not collide
577                                             * with other implementations' keys. E.g. A core called
578                                             * 'foo' should use keys named as 'foo_option'.
579                                             * retro_variable::value should contain a human readable
580                                             * description of the key as well as a '|' delimited list
581                                             * of expected values.
582                                             *
583                                             * The number of possible options should be very limited,
584                                             * i.e. it should be feasible to cycle through options
585                                             * without a keyboard.
586                                             *
587                                             * First entry should be treated as a default.
588                                             *
589                                             * Example entry:
590                                             * { "foo_option", "Speed hack coprocessor X; false|true" }
591                                             *
592                                             * Text before first ';' is description. This ';' must be
593                                             * followed by a space, and followed by a list of possible
594                                             * values split up with '|'.
595                                             *
596                                             * Only strings are operated on. The possible values will
597                                             * generally be displayed and stored as-is by the frontend.
598                                             */
599 #define RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE 17
600                                            /* bool * --
601                                             * Result is set to true if some variables are updated by
602                                             * frontend since last call to RETRO_ENVIRONMENT_GET_VARIABLE.
603                                             * Variables should be queried with GET_VARIABLE.
604                                             */
605 #define RETRO_ENVIRONMENT_SET_SUPPORT_NO_GAME 18
606                                            /* const bool * --
607                                             * If true, the libretro implementation supports calls to
608                                             * retro_load_game() with NULL as argument.
609                                             * Used by cores which can run without particular game data.
610                                             * This should be called within retro_set_environment() only.
611                                             */
612 #define RETRO_ENVIRONMENT_GET_LIBRETRO_PATH 19
613                                            /* const char ** --
614                                             * Retrieves the absolute path from where this libretro
615                                             * implementation was loaded.
616                                             * NULL is returned if the libretro was loaded statically
617                                             * (i.e. linked statically to frontend), or if the path cannot be
618                                             * determined.
619                                             * Mostly useful in cooperation with SET_SUPPORT_NO_GAME as assets can
620                                             * be loaded without ugly hacks.
621                                             */
622 
623                                            /* Environment 20 was an obsolete version of SET_AUDIO_CALLBACK.
624                                             * It was not used by any known core at the time,
625                                             * and was removed from the API. */
626 #define RETRO_ENVIRONMENT_SET_AUDIO_CALLBACK 22
627                                            /* const struct retro_audio_callback * --
628                                             * Sets an interface which is used to notify a libretro core about audio
629                                             * being available for writing.
630                                             * The callback can be called from any thread, so a core using this must
631                                             * have a thread safe audio implementation.
632                                             * It is intended for games where audio and video are completely
633                                             * asynchronous and audio can be generated on the fly.
634                                             * This interface is not recommended for use with emulators which have
635                                             * highly synchronous audio.
636                                             *
637                                             * The callback only notifies about writability; the libretro core still
638                                             * has to call the normal audio callbacks
639                                             * to write audio. The audio callbacks must be called from within the
640                                             * notification callback.
641                                             * The amount of audio data to write is up to the implementation.
642                                             * Generally, the audio callback will be called continously in a loop.
643                                             *
644                                             * Due to thread safety guarantees and lack of sync between audio and
645                                             * video, a frontend  can selectively disallow this interface based on
646                                             * internal configuration. A core using this interface must also
647                                             * implement the "normal" audio interface.
648                                             *
649                                             * A libretro core using SET_AUDIO_CALLBACK should also make use of
650                                             * SET_FRAME_TIME_CALLBACK.
651                                             */
652 #define RETRO_ENVIRONMENT_SET_FRAME_TIME_CALLBACK 21
653                                            /* const struct retro_frame_time_callback * --
654                                             * Lets the core know how much time has passed since last
655                                             * invocation of retro_run().
656                                             * The frontend can tamper with the timing to fake fast-forward,
657                                             * slow-motion, frame stepping, etc.
658                                             * In this case the delta time will use the reference value
659                                             * in frame_time_callback..
660                                             */
661 #define RETRO_ENVIRONMENT_GET_RUMBLE_INTERFACE 23
662                                            /* struct retro_rumble_interface * --
663                                             * Gets an interface which is used by a libretro core to set
664                                             * state of rumble motors in controllers.
665                                             * A strong and weak motor is supported, and they can be
666                                             * controlled indepedently.
667                                             */
668 #define RETRO_ENVIRONMENT_GET_INPUT_DEVICE_CAPABILITIES 24
669                                            /* uint64_t * --
670                                             * Gets a bitmask telling which device type are expected to be
671                                             * handled properly in a call to retro_input_state_t.
672                                             * Devices which are not handled or recognized always return
673                                             * 0 in retro_input_state_t.
674                                             * Example bitmask: caps = (1 << RETRO_DEVICE_JOYPAD) | (1 << RETRO_DEVICE_ANALOG).
675                                             * Should only be called in retro_run().
676                                             */
677 #define RETRO_ENVIRONMENT_GET_SENSOR_INTERFACE (25 | RETRO_ENVIRONMENT_EXPERIMENTAL)
678                                            /* struct retro_sensor_interface * --
679                                             * Gets access to the sensor interface.
680                                             * The purpose of this interface is to allow
681                                             * setting state related to sensors such as polling rate,
682                                             * enabling/disable it entirely, etc.
683                                             * Reading sensor state is done via the normal
684                                             * input_state_callback API.
685                                             */
686 #define RETRO_ENVIRONMENT_GET_CAMERA_INTERFACE (26 | RETRO_ENVIRONMENT_EXPERIMENTAL)
687                                            /* struct retro_camera_callback * --
688                                             * Gets an interface to a video camera driver.
689                                             * A libretro core can use this interface to get access to a
690                                             * video camera.
691                                             * New video frames are delivered in a callback in same
692                                             * thread as retro_run().
693                                             *
694                                             * GET_CAMERA_INTERFACE should be called in retro_load_game().
695                                             *
696                                             * Depending on the camera implementation used, camera frames
697                                             * will be delivered as a raw framebuffer,
698                                             * or as an OpenGL texture directly.
699                                             *
700                                             * The core has to tell the frontend here which types of
701                                             * buffers can be handled properly.
702                                             * An OpenGL texture can only be handled when using a
703                                             * libretro GL core (SET_HW_RENDER).
704                                             * It is recommended to use a libretro GL core when
705                                             * using camera interface.
706                                             *
707                                             * The camera is not started automatically. The retrieved start/stop
708                                             * functions must be used to explicitly
709                                             * start and stop the camera driver.
710                                             */
711 #define RETRO_ENVIRONMENT_GET_LOG_INTERFACE 27
712                                            /* struct retro_log_callback * --
713                                             * Gets an interface for logging. This is useful for
714                                             * logging in a cross-platform way
715                                             * as certain platforms cannot use use stderr for logging.
716                                             * It also allows the frontend to
717                                             * show logging information in a more suitable way.
718                                             * If this interface is not used, libretro cores should
719                                             * log to stderr as desired.
720                                             */
721 #define RETRO_ENVIRONMENT_GET_PERF_INTERFACE 28
722                                            /* struct retro_perf_callback * --
723                                             * Gets an interface for performance counters. This is useful
724                                             * for performance logging in a cross-platform way and for detecting
725                                             * architecture-specific features, such as SIMD support.
726                                             */
727 #define RETRO_ENVIRONMENT_GET_LOCATION_INTERFACE 29
728                                            /* struct retro_location_callback * --
729                                             * Gets access to the location interface.
730                                             * The purpose of this interface is to be able to retrieve
731                                             * location-based information from the host device,
732                                             * such as current latitude / longitude.
733                                             */
734 #define RETRO_ENVIRONMENT_GET_CONTENT_DIRECTORY 30 /* Old name, kept for compatibility. */
735 #define RETRO_ENVIRONMENT_GET_CORE_ASSETS_DIRECTORY 30
736                                            /* const char ** --
737                                             * Returns the "core assets" directory of the frontend.
738                                             * This directory can be used to store specific assets that the
739                                             * core relies upon, such as art assets,
740                                             * input data, etc etc.
741                                             * The returned value can be NULL.
742                                             * If so, no such directory is defined,
743                                             * and it's up to the implementation to find a suitable directory.
744                                             */
745 #define RETRO_ENVIRONMENT_GET_SAVE_DIRECTORY 31
746                                            /* const char ** --
747                                             * Returns the "save" directory of the frontend.
748                                             * This directory can be used to store SRAM, memory cards,
749                                             * high scores, etc, if the libretro core
750                                             * cannot use the regular memory interface (retro_get_memory_data()).
751                                             *
752                                             * NOTE: libretro cores used to check GET_SYSTEM_DIRECTORY for
753                                             * similar things before.
754                                             * They should still check GET_SYSTEM_DIRECTORY if they want to
755                                             * be backwards compatible.
756                                             * The path here can be NULL. It should only be non-NULL if the
757                                             * frontend user has set a specific save path.
758                                             */
759 #define RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO 32
760                                            /* const struct retro_system_av_info * --
761                                             * Sets a new av_info structure. This can only be called from
762                                             * within retro_run().
763                                             * This should *only* be used if the core is completely altering the
764                                             * internal resolutions, aspect ratios, timings, sampling rate, etc.
765                                             * Calling this can require a full reinitialization of video/audio
766                                             * drivers in the frontend,
767                                             *
768                                             * so it is important to call it very sparingly, and usually only with
769                                             * the users explicit consent.
770                                             * An eventual driver reinitialize will happen so that video and
771                                             * audio callbacks
772                                             * happening after this call within the same retro_run() call will
773                                             * target the newly initialized driver.
774                                             *
775                                             * This callback makes it possible to support configurable resolutions
776                                             * in games, which can be useful to
777                                             * avoid setting the "worst case" in max_width/max_height.
778                                             *
779                                             * ***HIGHLY RECOMMENDED*** Do not call this callback every time
780                                             * resolution changes in an emulator core if it's
781                                             * expected to be a temporary change, for the reasons of possible
782                                             * driver reinitialization.
783                                             * This call is not a free pass for not trying to provide
784                                             * correct values in retro_get_system_av_info(). If you need to change
785                                             * things like aspect ratio or nominal width/height,
786                                             * use RETRO_ENVIRONMENT_SET_GEOMETRY, which is a softer variant
787                                             * of SET_SYSTEM_AV_INFO.
788                                             *
789                                             * If this returns false, the frontend does not acknowledge a
790                                             * changed av_info struct.
791                                             */
792 #define RETRO_ENVIRONMENT_SET_PROC_ADDRESS_CALLBACK 33
793                                            /* const struct retro_get_proc_address_interface * --
794                                             * Allows a libretro core to announce support for the
795                                             * get_proc_address() interface.
796                                             * This interface allows for a standard way to extend libretro where
797                                             * use of environment calls are too indirect,
798                                             * e.g. for cases where the frontend wants to call directly into the core.
799                                             *
800                                             * If a core wants to expose this interface, SET_PROC_ADDRESS_CALLBACK
801                                             * **MUST** be called from within retro_set_environment().
802                                             */
803 #define RETRO_ENVIRONMENT_SET_SUBSYSTEM_INFO 34
804                                            /* const struct retro_subsystem_info * --
805                                             * This environment call introduces the concept of libretro "subsystems".
806                                             * A subsystem is a variant of a libretro core which supports
807                                             * different kinds of games.
808                                             * The purpose of this is to support e.g. emulators which might
809                                             * have special needs, e.g. Super Nintendo's Super GameBoy, Sufami Turbo.
810                                             * It can also be used to pick among subsystems in an explicit way
811                                             * if the libretro implementation is a multi-system emulator itself.
812                                             *
813                                             * Loading a game via a subsystem is done with retro_load_game_special(),
814                                             * and this environment call allows a libretro core to expose which
815                                             * subsystems are supported for use with retro_load_game_special().
816                                             * A core passes an array of retro_game_special_info which is terminated
817                                             * with a zeroed out retro_game_special_info struct.
818                                             *
819                                             * If a core wants to use this functionality, SET_SUBSYSTEM_INFO
820                                             * **MUST** be called from within retro_set_environment().
821                                             */
822 #define RETRO_ENVIRONMENT_SET_CONTROLLER_INFO 35
823                                            /* const struct retro_controller_info * --
824                                             * This environment call lets a libretro core tell the frontend
825                                             * which controller types are recognized in calls to
826                                             * retro_set_controller_port_device().
827                                             *
828                                             * Some emulators such as Super Nintendo
829                                             * support multiple lightgun types which must be specifically
830                                             * selected from.
831                                             * It is therefore sometimes necessary for a frontend to be able
832                                             * to tell the core about a special kind of input device which is
833                                             * not covered by the libretro input API.
834                                             *
835                                             * In order for a frontend to understand the workings of an input device,
836                                             * it must be a specialized type
837                                             * of the generic device types already defined in the libretro API.
838                                             *
839                                             * Which devices are supported can vary per input port.
840                                             * The core must pass an array of const struct retro_controller_info which
841                                             * is terminated with a blanked out struct. Each element of the struct
842                                             * corresponds to an ascending port index to
843                                             * retro_set_controller_port_device().
844                                             * Even if special device types are set in the libretro core,
845                                             * libretro should only poll input based on the base input device types.
846                                             */
847 #define RETRO_ENVIRONMENT_SET_MEMORY_MAPS (36 | RETRO_ENVIRONMENT_EXPERIMENTAL)
848                                            /* const struct retro_memory_map * --
849                                             * This environment call lets a libretro core tell the frontend
850                                             * about the memory maps this core emulates.
851                                             * This can be used to implement, for example, cheats in a core-agnostic way.
852                                             *
853                                             * Should only be used by emulators; it doesn't make much sense for
854                                             * anything else.
855                                             * It is recommended to expose all relevant pointers through
856                                             * retro_get_memory_* as well.
857                                             *
858                                             * Can be called from retro_init and retro_load_game.
859                                             */
860 #define RETRO_ENVIRONMENT_SET_GEOMETRY 37
861                                            /* const struct retro_game_geometry * --
862                                             * This environment call is similar to SET_SYSTEM_AV_INFO for changing
863                                             * video parameters, but provides a guarantee that drivers will not be
864                                             * reinitialized.
865                                             * This can only be called from within retro_run().
866                                             *
867                                             * The purpose of this call is to allow a core to alter nominal
868                                             * width/heights as well as aspect ratios on-the-fly, which can be
869                                             * useful for some emulators to change in run-time.
870                                             *
871                                             * max_width/max_height arguments are ignored and cannot be changed
872                                             * with this call as this could potentially require a reinitialization or a
873                                             * non-constant time operation.
874                                             * If max_width/max_height are to be changed, SET_SYSTEM_AV_INFO is required.
875                                             *
876                                             * A frontend must guarantee that this environment call completes in
877                                             * constant time.
878                                             */
879 #define RETRO_ENVIRONMENT_GET_USERNAME 38
880                                            /* const char **
881                                             * Returns the specified username of the frontend, if specified by the user.
882                                             * This username can be used as a nickname for a core that has online facilities
883                                             * or any other mode where personalization of the user is desirable.
884                                             * The returned value can be NULL.
885                                             * If this environ callback is used by a core that requires a valid username,
886                                             * a default username should be specified by the core.
887                                             */
888 #define RETRO_ENVIRONMENT_GET_LANGUAGE 39
889                                            /* unsigned * --
890                                             * Returns the specified language of the frontend, if specified by the user.
891                                             * It can be used by the core for localization purposes.
892                                             */
893 #define RETRO_ENVIRONMENT_GET_CURRENT_SOFTWARE_FRAMEBUFFER (40 | RETRO_ENVIRONMENT_EXPERIMENTAL)
894                                            /* struct retro_framebuffer * --
895                                             * Returns a preallocated framebuffer which the core can use for rendering
896                                             * the frame into when not using SET_HW_RENDER.
897                                             * The framebuffer returned from this call must not be used
898                                             * after the current call to retro_run() returns.
899                                             *
900                                             * The goal of this call is to allow zero-copy behavior where a core
901                                             * can render directly into video memory, avoiding extra bandwidth cost by copying
902                                             * memory from core to video memory.
903                                             *
904                                             * If this call succeeds and the core renders into it,
905                                             * the framebuffer pointer and pitch can be passed to retro_video_refresh_t.
906                                             * If the buffer from GET_CURRENT_SOFTWARE_FRAMEBUFFER is to be used,
907                                             * the core must pass the exact
908                                             * same pointer as returned by GET_CURRENT_SOFTWARE_FRAMEBUFFER;
909                                             * i.e. passing a pointer which is offset from the
910                                             * buffer is undefined. The width, height and pitch parameters
911                                             * must also match exactly to the values obtained from GET_CURRENT_SOFTWARE_FRAMEBUFFER.
912                                             *
913                                             * It is possible for a frontend to return a different pixel format
914                                             * than the one used in SET_PIXEL_FORMAT. This can happen if the frontend
915                                             * needs to perform conversion.
916                                             *
917                                             * It is still valid for a core to render to a different buffer
918                                             * even if GET_CURRENT_SOFTWARE_FRAMEBUFFER succeeds.
919                                             *
920                                             * A frontend must make sure that the pointer obtained from this function is
921                                             * writeable (and readable).
922                                             */
923 
924 enum retro_hw_render_interface_type
925 {
926    RETRO_HW_RENDER_INTERFACE_VULKAN = 0,
927    RETRO_HW_RENDER_INTERFACE_DUMMY = INT_MAX
928 };
929 
930 /* Base struct. All retro_hw_render_interface_* types
931  * contain at least these fields. */
932 struct retro_hw_render_interface
933 {
934    enum retro_hw_render_interface_type interface_type;
935    unsigned interface_version;
936 };
937 #define RETRO_ENVIRONMENT_GET_HW_RENDER_INTERFACE (41 | RETRO_ENVIRONMENT_EXPERIMENTAL)
938                                            /* const struct retro_hw_render_interface ** --
939                                             * Returns an API specific rendering interface for accessing API specific data.
940                                             * Not all HW rendering APIs support or need this.
941                                             * The contents of the returned pointer is specific to the rendering API
942                                             * being used. See the various headers like libretro_vulkan.h, etc.
943                                             *
944                                             * GET_HW_RENDER_INTERFACE cannot be called before context_reset has been called.
945                                             * Similarly, after context_destroyed callback returns,
946                                             * the contents of the HW_RENDER_INTERFACE are invalidated.
947                                             */
948 
949 #define RETRO_ENVIRONMENT_SET_SUPPORT_ACHIEVEMENTS (42 | RETRO_ENVIRONMENT_EXPERIMENTAL)
950                                            /* const bool * --
951                                             * If true, the libretro implementation supports achievements
952                                             * either via memory descriptors set with RETRO_ENVIRONMENT_SET_MEMORY_MAPS
953                                             * or via retro_get_memory_data/retro_get_memory_size.
954                                             *
955                                             * This must be called before the first call to retro_run.
956                                             */
957 
958 enum retro_hw_render_context_negotiation_interface_type
959 {
960    RETRO_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE_VULKAN = 0,
961    RETRO_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE_DUMMY = INT_MAX
962 };
963 
964 /* Base struct. All retro_hw_render_context_negotiation_interface_* types
965  * contain at least these fields. */
966 struct retro_hw_render_context_negotiation_interface
967 {
968    enum retro_hw_render_context_negotiation_interface_type interface_type;
969    unsigned interface_version;
970 };
971 #define RETRO_ENVIRONMENT_SET_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE (43 | RETRO_ENVIRONMENT_EXPERIMENTAL)
972                                            /* const struct retro_hw_render_context_negotiation_interface * --
973                                             * Sets an interface which lets the libretro core negotiate with frontend how a context is created.
974                                             * The semantics of this interface depends on which API is used in SET_HW_RENDER earlier.
975                                             * This interface will be used when the frontend is trying to create a HW rendering context,
976                                             * so it will be used after SET_HW_RENDER, but before the context_reset callback.
977                                             */
978 
979 /* Serialized state is incomplete in some way. Set if serialization is
980  * usable in typical end-user cases but should not be relied upon to
981  * implement frame-sensitive frontend features such as netplay or
982  * rerecording. */
983 #define RETRO_SERIALIZATION_QUIRK_INCOMPLETE (1 << 0)
984 /* The core must spend some time initializing before serialization is
985  * supported. retro_serialize() will initially fail; retro_unserialize()
986  * and retro_serialize_size() may or may not work correctly either. */
987 #define RETRO_SERIALIZATION_QUIRK_MUST_INITIALIZE (1 << 1)
988 /* Serialization size may change within a session. */
989 #define RETRO_SERIALIZATION_QUIRK_CORE_VARIABLE_SIZE (1 << 2)
990 /* Set by the frontend to acknowledge that it supports variable-sized
991  * states. */
992 #define RETRO_SERIALIZATION_QUIRK_FRONT_VARIABLE_SIZE (1 << 3)
993 /* Serialized state can only be loaded during the same session. */
994 #define RETRO_SERIALIZATION_QUIRK_SINGLE_SESSION (1 << 4)
995 /* Serialized state cannot be loaded on an architecture with a different
996  * endianness from the one it was saved on. */
997 #define RETRO_SERIALIZATION_QUIRK_ENDIAN_DEPENDENT (1 << 5)
998 /* Serialized state cannot be loaded on a different platform from the one it
999  * was saved on for reasons other than endianness, such as word size
1000  * dependence */
1001 #define RETRO_SERIALIZATION_QUIRK_PLATFORM_DEPENDENT (1 << 6)
1002 
1003 #define RETRO_ENVIRONMENT_SET_SERIALIZATION_QUIRKS 44
1004                                            /* uint64_t * --
1005                                             * Sets quirk flags associated with serialization. The frontend will zero any flags it doesn't
1006                                             * recognize or support. Should be set in either retro_init or retro_load_game, but not both.
1007                                             */
1008 
1009 
1010 #define RETRO_MEMDESC_CONST     (1 << 0)   /* The frontend will never change this memory area once retro_load_game has returned. */
1011 #define RETRO_MEMDESC_BIGENDIAN (1 << 1)   /* The memory area contains big endian data. Default is little endian. */
1012 #define RETRO_MEMDESC_ALIGN_2   (1 << 16)  /* All memory access in this area is aligned to their own size, or 2, whichever is smaller. */
1013 #define RETRO_MEMDESC_ALIGN_4   (2 << 16)
1014 #define RETRO_MEMDESC_ALIGN_8   (3 << 16)
1015 #define RETRO_MEMDESC_MINSIZE_2 (1 << 24)  /* All memory in this region is accessed at least 2 bytes at the time. */
1016 #define RETRO_MEMDESC_MINSIZE_4 (2 << 24)
1017 #define RETRO_MEMDESC_MINSIZE_8 (3 << 24)
1018 struct retro_memory_descriptor
1019 {
1020    uint64_t flags;
1021 
1022    /* Pointer to the start of the relevant ROM or RAM chip.
1023     * It's strongly recommended to use 'offset' if possible, rather than
1024     * doing math on the pointer.
1025     *
1026     * If the same byte is mapped my multiple descriptors, their descriptors
1027     * must have the same pointer.
1028     * If 'start' does not point to the first byte in the pointer, put the
1029     * difference in 'offset' instead.
1030     *
1031     * May be NULL if there's nothing usable here (e.g. hardware registers and
1032     * open bus). No flags should be set if the pointer is NULL.
1033     * It's recommended to minimize the number of descriptors if possible,
1034     * but not mandatory. */
1035    void *ptr;
1036    size_t offset;
1037 
1038    /* This is the location in the emulated address space
1039     * where the mapping starts. */
1040    size_t start;
1041 
1042    /* Which bits must be same as in 'start' for this mapping to apply.
1043     * The first memory descriptor to claim a certain byte is the one
1044     * that applies.
1045     * A bit which is set in 'start' must also be set in this.
1046     * Can be zero, in which case each byte is assumed mapped exactly once.
1047     * In this case, 'len' must be a power of two. */
1048    size_t select;
1049 
1050    /* If this is nonzero, the set bits are assumed not connected to the
1051     * memory chip's address pins. */
1052    size_t disconnect;
1053 
1054    /* This one tells the size of the current memory area.
1055     * If, after start+disconnect are applied, the address is higher than
1056     * this, the highest bit of the address is cleared.
1057     *
1058     * If the address is still too high, the next highest bit is cleared.
1059     * Can be zero, in which case it's assumed to be infinite (as limited
1060     * by 'select' and 'disconnect'). */
1061    size_t len;
1062 
1063    /* To go from emulated address to physical address, the following
1064     * order applies:
1065     * Subtract 'start', pick off 'disconnect', apply 'len', add 'offset'. */
1066 
1067    /* The address space name must consist of only a-zA-Z0-9_-,
1068     * should be as short as feasible (maximum length is 8 plus the NUL),
1069     * and may not be any other address space plus one or more 0-9A-F
1070     * at the end.
1071     * However, multiple memory descriptors for the same address space is
1072     * allowed, and the address space name can be empty. NULL is treated
1073     * as empty.
1074     *
1075     * Address space names are case sensitive, but avoid lowercase if possible.
1076     * The same pointer may exist in multiple address spaces.
1077     *
1078     * Examples:
1079     * blank+blank - valid (multiple things may be mapped in the same namespace)
1080     * 'Sp'+'Sp' - valid (multiple things may be mapped in the same namespace)
1081     * 'A'+'B' - valid (neither is a prefix of each other)
1082     * 'S'+blank - valid ('S' is not in 0-9A-F)
1083     * 'a'+blank - valid ('a' is not in 0-9A-F)
1084     * 'a'+'A' - valid (neither is a prefix of each other)
1085     * 'AR'+blank - valid ('R' is not in 0-9A-F)
1086     * 'ARB'+blank - valid (the B can't be part of the address either, because
1087     *                      there is no namespace 'AR')
1088     * blank+'B' - not valid, because it's ambigous which address space B1234
1089     *             would refer to.
1090     * The length can't be used for that purpose; the frontend may want
1091     * to append arbitrary data to an address, without a separator. */
1092    const char *addrspace;
1093 
1094    /* TODO: When finalizing this one, add a description field, which should be
1095     * "WRAM" or something roughly equally long. */
1096 
1097    /* TODO: When finalizing this one, replace 'select' with 'limit', which tells
1098     * which bits can vary and still refer to the same address (limit = ~select).
1099     * TODO: limit? range? vary? something else? */
1100 
1101    /* TODO: When finalizing this one, if 'len' is above what 'select' (or
1102     * 'limit') allows, it's bankswitched. Bankswitched data must have both 'len'
1103     * and 'select' != 0, and the mappings don't tell how the system switches the
1104     * banks. */
1105 
1106    /* TODO: When finalizing this one, fix the 'len' bit removal order.
1107     * For len=0x1800, pointer 0x1C00 should go to 0x1400, not 0x0C00.
1108     * Algorithm: Take bits highest to lowest, but if it goes above len, clear
1109     * the most recent addition and continue on the next bit.
1110     * TODO: Can the above be optimized? Is "remove the lowest bit set in both
1111     * pointer and 'len'" equivalent? */
1112 
1113    /* TODO: Some emulators (MAME?) emulate big endian systems by only accessing
1114     * the emulated memory in 32-bit chunks, native endian. But that's nothing
1115     * compared to Darek Mihocka <http://www.emulators.com/docs/nx07_vm101.htm>
1116     * (section Emulation 103 - Nearly Free Byte Reversal) - he flips the ENTIRE
1117     * RAM backwards! I'll want to represent both of those, via some flags.
1118     *
1119     * I suspect MAME either didn't think of that idea, or don't want the #ifdef.
1120     * Not sure which, nor do I really care. */
1121 
1122    /* TODO: Some of those flags are unused and/or don't really make sense. Clean
1123     * them up. */
1124 };
1125 
1126 /* The frontend may use the largest value of 'start'+'select' in a
1127  * certain namespace to infer the size of the address space.
1128  *
1129  * If the address space is larger than that, a mapping with .ptr=NULL
1130  * should be at the end of the array, with .select set to all ones for
1131  * as long as the address space is big.
1132  *
1133  * Sample descriptors (minus .ptr, and RETRO_MEMFLAG_ on the flags):
1134  * SNES WRAM:
1135  * .start=0x7E0000, .len=0x20000
1136  * (Note that this must be mapped before the ROM in most cases; some of the
1137  * ROM mappers
1138  * try to claim $7E0000, or at least $7E8000.)
1139  * SNES SPC700 RAM:
1140  * .addrspace="S", .len=0x10000
1141  * SNES WRAM mirrors:
1142  * .flags=MIRROR, .start=0x000000, .select=0xC0E000, .len=0x2000
1143  * .flags=MIRROR, .start=0x800000, .select=0xC0E000, .len=0x2000
1144  * SNES WRAM mirrors, alternate equivalent descriptor:
1145  * .flags=MIRROR, .select=0x40E000, .disconnect=~0x1FFF
1146  * (Various similar constructions can be created by combining parts of
1147  * the above two.)
1148  * SNES LoROM (512KB, mirrored a couple of times):
1149  * .flags=CONST, .start=0x008000, .select=0x408000, .disconnect=0x8000, .len=512*1024
1150  * .flags=CONST, .start=0x400000, .select=0x400000, .disconnect=0x8000, .len=512*1024
1151  * SNES HiROM (4MB):
1152  * .flags=CONST,                 .start=0x400000, .select=0x400000, .len=4*1024*1024
1153  * .flags=CONST, .offset=0x8000, .start=0x008000, .select=0x408000, .len=4*1024*1024
1154  * SNES ExHiROM (8MB):
1155  * .flags=CONST, .offset=0,                  .start=0xC00000, .select=0xC00000, .len=4*1024*1024
1156  * .flags=CONST, .offset=4*1024*1024,        .start=0x400000, .select=0xC00000, .len=4*1024*1024
1157  * .flags=CONST, .offset=0x8000,             .start=0x808000, .select=0xC08000, .len=4*1024*1024
1158  * .flags=CONST, .offset=4*1024*1024+0x8000, .start=0x008000, .select=0xC08000, .len=4*1024*1024
1159  * Clarify the size of the address space:
1160  * .ptr=NULL, .select=0xFFFFFF
1161  * .len can be implied by .select in many of them, but was included for clarity.
1162  */
1163 
1164 struct retro_memory_map
1165 {
1166    const struct retro_memory_descriptor *descriptors;
1167    unsigned num_descriptors;
1168 };
1169 
1170 struct retro_controller_description
1171 {
1172    /* Human-readable description of the controller. Even if using a generic
1173     * input device type, this can be set to the particular device type the
1174     * core uses. */
1175    const char *desc;
1176 
1177    /* Device type passed to retro_set_controller_port_device(). If the device
1178     * type is a sub-class of a generic input device type, use the
1179     * RETRO_DEVICE_SUBCLASS macro to create an ID.
1180     *
1181     * E.g. RETRO_DEVICE_SUBCLASS(RETRO_DEVICE_JOYPAD, 1). */
1182    unsigned id;
1183 };
1184 
1185 struct retro_controller_info
1186 {
1187    const struct retro_controller_description *types;
1188    unsigned num_types;
1189 };
1190 
1191 struct retro_subsystem_memory_info
1192 {
1193    /* The extension associated with a memory type, e.g. "psram". */
1194    const char *extension;
1195 
1196    /* The memory type for retro_get_memory(). This should be at
1197     * least 0x100 to avoid conflict with standardized
1198     * libretro memory types. */
1199    unsigned type;
1200 };
1201 
1202 struct retro_subsystem_rom_info
1203 {
1204    /* Describes what the content is (SGB BIOS, GB ROM, etc). */
1205    const char *desc;
1206 
1207    /* Same definition as retro_get_system_info(). */
1208    const char *valid_extensions;
1209 
1210    /* Same definition as retro_get_system_info(). */
1211    bool need_fullpath;
1212 
1213    /* Same definition as retro_get_system_info(). */
1214    bool block_extract;
1215 
1216    /* This is set if the content is required to load a game.
1217     * If this is set to false, a zeroed-out retro_game_info can be passed. */
1218    bool required;
1219 
1220    /* Content can have multiple associated persistent
1221     * memory types (retro_get_memory()). */
1222    const struct retro_subsystem_memory_info *memory;
1223    unsigned num_memory;
1224 };
1225 
1226 struct retro_subsystem_info
1227 {
1228    /* Human-readable string of the subsystem type, e.g. "Super GameBoy" */
1229    const char *desc;
1230 
1231    /* A computer friendly short string identifier for the subsystem type.
1232     * This name must be [a-z].
1233     * E.g. if desc is "Super GameBoy", this can be "sgb".
1234     * This identifier can be used for command-line interfaces, etc.
1235     */
1236    const char *ident;
1237 
1238    /* Infos for each content file. The first entry is assumed to be the
1239     * "most significant" content for frontend purposes.
1240     * E.g. with Super GameBoy, the first content should be the GameBoy ROM,
1241     * as it is the most "significant" content to a user.
1242     * If a frontend creates new file paths based on the content used
1243     * (e.g. savestates), it should use the path for the first ROM to do so. */
1244    const struct retro_subsystem_rom_info *roms;
1245 
1246    /* Number of content files associated with a subsystem. */
1247    unsigned num_roms;
1248 
1249    /* The type passed to retro_load_game_special(). */
1250    unsigned id;
1251 };
1252 
1253 typedef void (RETRO_CALLCONV *retro_proc_address_t)(void);
1254 
1255 /* libretro API extension functions:
1256  * (None here so far).
1257  *
1258  * Get a symbol from a libretro core.
1259  * Cores should only return symbols which are actual
1260  * extensions to the libretro API.
1261  *
1262  * Frontends should not use this to obtain symbols to standard
1263  * libretro entry points (static linking or dlsym).
1264  *
1265  * The symbol name must be equal to the function name,
1266  * e.g. if void retro_foo(void); exists, the symbol must be called "retro_foo".
1267  * The returned function pointer must be cast to the corresponding type.
1268  */
1269 typedef retro_proc_address_t (RETRO_CALLCONV *retro_get_proc_address_t)(const char *sym);
1270 
1271 struct retro_get_proc_address_interface
1272 {
1273    retro_get_proc_address_t get_proc_address;
1274 };
1275 
1276 enum retro_log_level
1277 {
1278    RETRO_LOG_DEBUG = 0,
1279    RETRO_LOG_INFO,
1280    RETRO_LOG_WARN,
1281    RETRO_LOG_ERROR,
1282 
1283    RETRO_LOG_DUMMY = INT_MAX
1284 };
1285 
1286 /* Logging function. Takes log level argument as well. */
1287 typedef void (RETRO_CALLCONV *retro_log_printf_t)(enum retro_log_level level,
1288       const char *fmt, ...);
1289 
1290 struct retro_log_callback
1291 {
1292    retro_log_printf_t log;
1293 };
1294 
1295 /* Performance related functions */
1296 
1297 /* ID values for SIMD CPU features */
1298 #define RETRO_SIMD_SSE      (1 << 0)
1299 #define RETRO_SIMD_SSE2     (1 << 1)
1300 #define RETRO_SIMD_VMX      (1 << 2)
1301 #define RETRO_SIMD_VMX128   (1 << 3)
1302 #define RETRO_SIMD_AVX      (1 << 4)
1303 #define RETRO_SIMD_NEON     (1 << 5)
1304 #define RETRO_SIMD_SSE3     (1 << 6)
1305 #define RETRO_SIMD_SSSE3    (1 << 7)
1306 #define RETRO_SIMD_MMX      (1 << 8)
1307 #define RETRO_SIMD_MMXEXT   (1 << 9)
1308 #define RETRO_SIMD_SSE4     (1 << 10)
1309 #define RETRO_SIMD_SSE42    (1 << 11)
1310 #define RETRO_SIMD_AVX2     (1 << 12)
1311 #define RETRO_SIMD_VFPU     (1 << 13)
1312 #define RETRO_SIMD_PS       (1 << 14)
1313 #define RETRO_SIMD_AES      (1 << 15)
1314 #define RETRO_SIMD_VFPV3    (1 << 16)
1315 #define RETRO_SIMD_VFPV4    (1 << 17)
1316 #define RETRO_SIMD_POPCNT   (1 << 18)
1317 #define RETRO_SIMD_MOVBE    (1 << 19)
1318 #define RETRO_SIMD_CMOV     (1 << 20)
1319 #define RETRO_SIMD_ASIMD    (1 << 21)
1320 
1321 typedef uint64_t retro_perf_tick_t;
1322 typedef int64_t retro_time_t;
1323 
1324 struct retro_perf_counter
1325 {
1326    const char *ident;
1327    retro_perf_tick_t start;
1328    retro_perf_tick_t total;
1329    retro_perf_tick_t call_cnt;
1330 
1331    bool registered;
1332 };
1333 
1334 /* Returns current time in microseconds.
1335  * Tries to use the most accurate timer available.
1336  */
1337 typedef retro_time_t (RETRO_CALLCONV *retro_perf_get_time_usec_t)(void);
1338 
1339 /* A simple counter. Usually nanoseconds, but can also be CPU cycles.
1340  * Can be used directly if desired (when creating a more sophisticated
1341  * performance counter system).
1342  * */
1343 typedef retro_perf_tick_t (RETRO_CALLCONV *retro_perf_get_counter_t)(void);
1344 
1345 /* Returns a bit-mask of detected CPU features (RETRO_SIMD_*). */
1346 typedef uint64_t (RETRO_CALLCONV *retro_get_cpu_features_t)(void);
1347 
1348 /* Asks frontend to log and/or display the state of performance counters.
1349  * Performance counters can always be poked into manually as well.
1350  */
1351 typedef void (RETRO_CALLCONV *retro_perf_log_t)(void);
1352 
1353 /* Register a performance counter.
1354  * ident field must be set with a discrete value and other values in
1355  * retro_perf_counter must be 0.
1356  * Registering can be called multiple times. To avoid calling to
1357  * frontend redundantly, you can check registered field first. */
1358 typedef void (RETRO_CALLCONV *retro_perf_register_t)(struct retro_perf_counter *counter);
1359 
1360 /* Starts a registered counter. */
1361 typedef void (RETRO_CALLCONV *retro_perf_start_t)(struct retro_perf_counter *counter);
1362 
1363 /* Stops a registered counter. */
1364 typedef void (RETRO_CALLCONV *retro_perf_stop_t)(struct retro_perf_counter *counter);
1365 
1366 /* For convenience it can be useful to wrap register, start and stop in macros.
1367  * E.g.:
1368  * #ifdef LOG_PERFORMANCE
1369  * #define RETRO_PERFORMANCE_INIT(perf_cb, name) static struct retro_perf_counter name = {#name}; if (!name.registered) perf_cb.perf_register(&(name))
1370  * #define RETRO_PERFORMANCE_START(perf_cb, name) perf_cb.perf_start(&(name))
1371  * #define RETRO_PERFORMANCE_STOP(perf_cb, name) perf_cb.perf_stop(&(name))
1372  * #else
1373  * ... Blank macros ...
1374  * #endif
1375  *
1376  * These can then be used mid-functions around code snippets.
1377  *
1378  * extern struct retro_perf_callback perf_cb;  * Somewhere in the core.
1379  *
1380  * void do_some_heavy_work(void)
1381  * {
1382  *    RETRO_PERFORMANCE_INIT(cb, work_1;
1383  *    RETRO_PERFORMANCE_START(cb, work_1);
1384  *    heavy_work_1();
1385  *    RETRO_PERFORMANCE_STOP(cb, work_1);
1386  *
1387  *    RETRO_PERFORMANCE_INIT(cb, work_2);
1388  *    RETRO_PERFORMANCE_START(cb, work_2);
1389  *    heavy_work_2();
1390  *    RETRO_PERFORMANCE_STOP(cb, work_2);
1391  * }
1392  *
1393  * void retro_deinit(void)
1394  * {
1395  *    perf_cb.perf_log();  * Log all perf counters here for example.
1396  * }
1397  */
1398 
1399 struct retro_perf_callback
1400 {
1401    retro_perf_get_time_usec_t    get_time_usec;
1402    retro_get_cpu_features_t      get_cpu_features;
1403 
1404    retro_perf_get_counter_t      get_perf_counter;
1405    retro_perf_register_t         perf_register;
1406    retro_perf_start_t            perf_start;
1407    retro_perf_stop_t             perf_stop;
1408    retro_perf_log_t              perf_log;
1409 };
1410 
1411 /* FIXME: Document the sensor API and work out behavior.
1412  * It will be marked as experimental until then.
1413  */
1414 enum retro_sensor_action
1415 {
1416    RETRO_SENSOR_ACCELEROMETER_ENABLE = 0,
1417    RETRO_SENSOR_ACCELEROMETER_DISABLE,
1418 
1419    RETRO_SENSOR_DUMMY = INT_MAX
1420 };
1421 
1422 /* Id values for SENSOR types. */
1423 #define RETRO_SENSOR_ACCELEROMETER_X 0
1424 #define RETRO_SENSOR_ACCELEROMETER_Y 1
1425 #define RETRO_SENSOR_ACCELEROMETER_Z 2
1426 
1427 typedef bool (RETRO_CALLCONV *retro_set_sensor_state_t)(unsigned port,
1428       enum retro_sensor_action action, unsigned rate);
1429 
1430 typedef float (RETRO_CALLCONV *retro_sensor_get_input_t)(unsigned port, unsigned id);
1431 
1432 struct retro_sensor_interface
1433 {
1434    retro_set_sensor_state_t set_sensor_state;
1435    retro_sensor_get_input_t get_sensor_input;
1436 };
1437 
1438 enum retro_camera_buffer
1439 {
1440    RETRO_CAMERA_BUFFER_OPENGL_TEXTURE = 0,
1441    RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER,
1442 
1443    RETRO_CAMERA_BUFFER_DUMMY = INT_MAX
1444 };
1445 
1446 /* Starts the camera driver. Can only be called in retro_run(). */
1447 typedef bool (RETRO_CALLCONV *retro_camera_start_t)(void);
1448 
1449 /* Stops the camera driver. Can only be called in retro_run(). */
1450 typedef void (RETRO_CALLCONV *retro_camera_stop_t)(void);
1451 
1452 /* Callback which signals when the camera driver is initialized
1453  * and/or deinitialized.
1454  * retro_camera_start_t can be called in initialized callback.
1455  */
1456 typedef void (RETRO_CALLCONV *retro_camera_lifetime_status_t)(void);
1457 
1458 /* A callback for raw framebuffer data. buffer points to an XRGB8888 buffer.
1459  * Width, height and pitch are similar to retro_video_refresh_t.
1460  * First pixel is top-left origin.
1461  */
1462 typedef void (RETRO_CALLCONV *retro_camera_frame_raw_framebuffer_t)(const uint32_t *buffer,
1463       unsigned width, unsigned height, size_t pitch);
1464 
1465 /* A callback for when OpenGL textures are used.
1466  *
1467  * texture_id is a texture owned by camera driver.
1468  * Its state or content should be considered immutable, except for things like
1469  * texture filtering and clamping.
1470  *
1471  * texture_target is the texture target for the GL texture.
1472  * These can include e.g. GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE, and possibly
1473  * more depending on extensions.
1474  *
1475  * affine points to a packed 3x3 column-major matrix used to apply an affine
1476  * transform to texture coordinates. (affine_matrix * vec3(coord_x, coord_y, 1.0))
1477  * After transform, normalized texture coord (0, 0) should be bottom-left
1478  * and (1, 1) should be top-right (or (width, height) for RECTANGLE).
1479  *
1480  * GL-specific typedefs are avoided here to avoid relying on gl.h in
1481  * the API definition.
1482  */
1483 typedef void (RETRO_CALLCONV *retro_camera_frame_opengl_texture_t)(unsigned texture_id,
1484       unsigned texture_target, const float *affine);
1485 
1486 struct retro_camera_callback
1487 {
1488    /* Set by libretro core.
1489     * Example bitmask: caps = (1 << RETRO_CAMERA_BUFFER_OPENGL_TEXTURE) | (1 << RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER).
1490     */
1491    uint64_t caps;
1492 
1493    /* Desired resolution for camera. Is only used as a hint. */
1494    unsigned width;
1495    unsigned height;
1496 
1497    /* Set by frontend. */
1498    retro_camera_start_t start;
1499    retro_camera_stop_t stop;
1500 
1501    /* Set by libretro core if raw framebuffer callbacks will be used. */
1502    retro_camera_frame_raw_framebuffer_t frame_raw_framebuffer;
1503 
1504    /* Set by libretro core if OpenGL texture callbacks will be used. */
1505    retro_camera_frame_opengl_texture_t frame_opengl_texture;
1506 
1507    /* Set by libretro core. Called after camera driver is initialized and
1508     * ready to be started.
1509     * Can be NULL, in which this callback is not called.
1510     */
1511    retro_camera_lifetime_status_t initialized;
1512 
1513    /* Set by libretro core. Called right before camera driver is
1514     * deinitialized.
1515     * Can be NULL, in which this callback is not called.
1516     */
1517    retro_camera_lifetime_status_t deinitialized;
1518 };
1519 
1520 /* Sets the interval of time and/or distance at which to update/poll
1521  * location-based data.
1522  *
1523  * To ensure compatibility with all location-based implementations,
1524  * values for both interval_ms and interval_distance should be provided.
1525  *
1526  * interval_ms is the interval expressed in milliseconds.
1527  * interval_distance is the distance interval expressed in meters.
1528  */
1529 typedef void (RETRO_CALLCONV *retro_location_set_interval_t)(unsigned interval_ms,
1530       unsigned interval_distance);
1531 
1532 /* Start location services. The device will start listening for changes to the
1533  * current location at regular intervals (which are defined with
1534  * retro_location_set_interval_t). */
1535 typedef bool (RETRO_CALLCONV *retro_location_start_t)(void);
1536 
1537 /* Stop location services. The device will stop listening for changes
1538  * to the current location. */
1539 typedef void (RETRO_CALLCONV *retro_location_stop_t)(void);
1540 
1541 /* Get the position of the current location. Will set parameters to
1542  * 0 if no new  location update has happened since the last time. */
1543 typedef bool (RETRO_CALLCONV *retro_location_get_position_t)(double *lat, double *lon,
1544       double *horiz_accuracy, double *vert_accuracy);
1545 
1546 /* Callback which signals when the location driver is initialized
1547  * and/or deinitialized.
1548  * retro_location_start_t can be called in initialized callback.
1549  */
1550 typedef void (RETRO_CALLCONV *retro_location_lifetime_status_t)(void);
1551 
1552 struct retro_location_callback
1553 {
1554    retro_location_start_t         start;
1555    retro_location_stop_t          stop;
1556    retro_location_get_position_t  get_position;
1557    retro_location_set_interval_t  set_interval;
1558 
1559    retro_location_lifetime_status_t initialized;
1560    retro_location_lifetime_status_t deinitialized;
1561 };
1562 
1563 enum retro_rumble_effect
1564 {
1565    RETRO_RUMBLE_STRONG = 0,
1566    RETRO_RUMBLE_WEAK = 1,
1567 
1568    RETRO_RUMBLE_DUMMY = INT_MAX
1569 };
1570 
1571 /* Sets rumble state for joypad plugged in port 'port'.
1572  * Rumble effects are controlled independently,
1573  * and setting e.g. strong rumble does not override weak rumble.
1574  * Strength has a range of [0, 0xffff].
1575  *
1576  * Returns true if rumble state request was honored.
1577  * Calling this before first retro_run() is likely to return false. */
1578 typedef bool (RETRO_CALLCONV *retro_set_rumble_state_t)(unsigned port,
1579       enum retro_rumble_effect effect, uint16_t strength);
1580 
1581 struct retro_rumble_interface
1582 {
1583    retro_set_rumble_state_t set_rumble_state;
1584 };
1585 
1586 /* Notifies libretro that audio data should be written. */
1587 typedef void (RETRO_CALLCONV *retro_audio_callback_t)(void);
1588 
1589 /* True: Audio driver in frontend is active, and callback is
1590  * expected to be called regularily.
1591  * False: Audio driver in frontend is paused or inactive.
1592  * Audio callback will not be called until set_state has been
1593  * called with true.
1594  * Initial state is false (inactive).
1595  */
1596 typedef void (RETRO_CALLCONV *retro_audio_set_state_callback_t)(bool enabled);
1597 
1598 struct retro_audio_callback
1599 {
1600    retro_audio_callback_t callback;
1601    retro_audio_set_state_callback_t set_state;
1602 };
1603 
1604 /* Notifies a libretro core of time spent since last invocation
1605  * of retro_run() in microseconds.
1606  *
1607  * It will be called right before retro_run() every frame.
1608  * The frontend can tamper with timing to support cases like
1609  * fast-forward, slow-motion and framestepping.
1610  *
1611  * In those scenarios the reference frame time value will be used. */
1612 typedef int64_t retro_usec_t;
1613 typedef void (RETRO_CALLCONV *retro_frame_time_callback_t)(retro_usec_t usec);
1614 struct retro_frame_time_callback
1615 {
1616    retro_frame_time_callback_t callback;
1617    /* Represents the time of one frame. It is computed as
1618     * 1000000 / fps, but the implementation will resolve the
1619     * rounding to ensure that framestepping, etc is exact. */
1620    retro_usec_t reference;
1621 };
1622 
1623 /* Pass this to retro_video_refresh_t if rendering to hardware.
1624  * Passing NULL to retro_video_refresh_t is still a frame dupe as normal.
1625  * */
1626 #define RETRO_HW_FRAME_BUFFER_VALID ((void*)-1)
1627 
1628 /* Invalidates the current HW context.
1629  * Any GL state is lost, and must not be deinitialized explicitly.
1630  * If explicit deinitialization is desired by the libretro core,
1631  * it should implement context_destroy callback.
1632  * If called, all GPU resources must be reinitialized.
1633  * Usually called when frontend reinits video driver.
1634  * Also called first time video driver is initialized,
1635  * allowing libretro core to initialize resources.
1636  */
1637 typedef void (RETRO_CALLCONV *retro_hw_context_reset_t)(void);
1638 
1639 /* Gets current framebuffer which is to be rendered to.
1640  * Could change every frame potentially.
1641  */
1642 typedef uintptr_t (RETRO_CALLCONV *retro_hw_get_current_framebuffer_t)(void);
1643 
1644 /* Get a symbol from HW context. */
1645 typedef retro_proc_address_t (RETRO_CALLCONV *retro_hw_get_proc_address_t)(const char *sym);
1646 
1647 enum retro_hw_context_type
1648 {
1649    RETRO_HW_CONTEXT_NONE             = 0,
1650    /* OpenGL 2.x. Driver can choose to use latest compatibility context. */
1651    RETRO_HW_CONTEXT_OPENGL           = 1,
1652    /* OpenGL ES 2.0. */
1653    RETRO_HW_CONTEXT_OPENGLES2        = 2,
1654    /* Modern desktop core GL context. Use version_major/
1655     * version_minor fields to set GL version. */
1656    RETRO_HW_CONTEXT_OPENGL_CORE      = 3,
1657    /* OpenGL ES 3.0 */
1658    RETRO_HW_CONTEXT_OPENGLES3        = 4,
1659    /* OpenGL ES 3.1+. Set version_major/version_minor. For GLES2 and GLES3,
1660     * use the corresponding enums directly. */
1661    RETRO_HW_CONTEXT_OPENGLES_VERSION = 5,
1662 
1663    /* Vulkan, see RETRO_ENVIRONMENT_GET_HW_RENDER_INTERFACE. */
1664    RETRO_HW_CONTEXT_VULKAN           = 6,
1665 
1666    RETRO_HW_CONTEXT_DUMMY = INT_MAX
1667 };
1668 
1669 struct retro_hw_render_callback
1670 {
1671    /* Which API to use. Set by libretro core. */
1672    enum retro_hw_context_type context_type;
1673 
1674    /* Called when a context has been created or when it has been reset.
1675     * An OpenGL context is only valid after context_reset() has been called.
1676     *
1677     * When context_reset is called, OpenGL resources in the libretro
1678     * implementation are guaranteed to be invalid.
1679     *
1680     * It is possible that context_reset is called multiple times during an
1681     * application lifecycle.
1682     * If context_reset is called without any notification (context_destroy),
1683     * the OpenGL context was lost and resources should just be recreated
1684     * without any attempt to "free" old resources.
1685     */
1686    retro_hw_context_reset_t context_reset;
1687 
1688    /* Set by frontend.
1689     * TODO: This is rather obsolete. The frontend should not
1690     * be providing preallocated framebuffers. */
1691    retro_hw_get_current_framebuffer_t get_current_framebuffer;
1692 
1693    /* Set by frontend. */
1694    retro_hw_get_proc_address_t get_proc_address;
1695 
1696    /* Set if render buffers should have depth component attached.
1697     * TODO: Obsolete. */
1698    bool depth;
1699 
1700    /* Set if stencil buffers should be attached.
1701     * TODO: Obsolete. */
1702    bool stencil;
1703 
1704    /* If depth and stencil are true, a packed 24/8 buffer will be added.
1705     * Only attaching stencil is invalid and will be ignored. */
1706 
1707    /* Use conventional bottom-left origin convention. If false,
1708     * standard libretro top-left origin semantics are used.
1709     * TODO: Move to GL specific interface. */
1710    bool bottom_left_origin;
1711 
1712    /* Major version number for core GL context or GLES 3.1+. */
1713    unsigned version_major;
1714 
1715    /* Minor version number for core GL context or GLES 3.1+. */
1716    unsigned version_minor;
1717 
1718    /* If this is true, the frontend will go very far to avoid
1719     * resetting context in scenarios like toggling fullscreen, etc.
1720     * TODO: Obsolete? Maybe frontend should just always assume this ...
1721     */
1722    bool cache_context;
1723 
1724    /* The reset callback might still be called in extreme situations
1725     * such as if the context is lost beyond recovery.
1726     *
1727     * For optimal stability, set this to false, and allow context to be
1728     * reset at any time.
1729     */
1730 
1731    /* A callback to be called before the context is destroyed in a
1732     * controlled way by the frontend. */
1733    retro_hw_context_reset_t context_destroy;
1734 
1735    /* OpenGL resources can be deinitialized cleanly at this step.
1736     * context_destroy can be set to NULL, in which resources will
1737     * just be destroyed without any notification.
1738     *
1739     * Even when context_destroy is non-NULL, it is possible that
1740     * context_reset is called without any destroy notification.
1741     * This happens if context is lost by external factors (such as
1742     * notified by GL_ARB_robustness).
1743     *
1744     * In this case, the context is assumed to be already dead,
1745     * and the libretro implementation must not try to free any OpenGL
1746     * resources in the subsequent context_reset.
1747     */
1748 
1749    /* Creates a debug context. */
1750    bool debug_context;
1751 };
1752 
1753 /* Callback type passed in RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK.
1754  * Called by the frontend in response to keyboard events.
1755  * down is set if the key is being pressed, or false if it is being released.
1756  * keycode is the RETROK value of the char.
1757  * character is the text character of the pressed key. (UTF-32).
1758  * key_modifiers is a set of RETROKMOD values or'ed together.
1759  *
1760  * The pressed/keycode state can be indepedent of the character.
1761  * It is also possible that multiple characters are generated from a
1762  * single keypress.
1763  * Keycode events should be treated separately from character events.
1764  * However, when possible, the frontend should try to synchronize these.
1765  * If only a character is posted, keycode should be RETROK_UNKNOWN.
1766  *
1767  * Similarily if only a keycode event is generated with no corresponding
1768  * character, character should be 0.
1769  */
1770 typedef void (RETRO_CALLCONV *retro_keyboard_event_t)(bool down, unsigned keycode,
1771       uint32_t character, uint16_t key_modifiers);
1772 
1773 struct retro_keyboard_callback
1774 {
1775    retro_keyboard_event_t callback;
1776 };
1777 
1778 /* Callbacks for RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE.
1779  * Should be set for implementations which can swap out multiple disk
1780  * images in runtime.
1781  *
1782  * If the implementation can do this automatically, it should strive to do so.
1783  * However, there are cases where the user must manually do so.
1784  *
1785  * Overview: To swap a disk image, eject the disk image with
1786  * set_eject_state(true).
1787  * Set the disk index with set_image_index(index). Insert the disk again
1788  * with set_eject_state(false).
1789  */
1790 
1791 /* If ejected is true, "ejects" the virtual disk tray.
1792  * When ejected, the disk image index can be set.
1793  */
1794 typedef bool (RETRO_CALLCONV *retro_set_eject_state_t)(bool ejected);
1795 
1796 /* Gets current eject state. The initial state is 'not ejected'. */
1797 typedef bool (RETRO_CALLCONV *retro_get_eject_state_t)(void);
1798 
1799 /* Gets current disk index. First disk is index 0.
1800  * If return value is >= get_num_images(), no disk is currently inserted.
1801  */
1802 typedef unsigned (RETRO_CALLCONV *retro_get_image_index_t)(void);
1803 
1804 /* Sets image index. Can only be called when disk is ejected.
1805  * The implementation supports setting "no disk" by using an
1806  * index >= get_num_images().
1807  */
1808 typedef bool (RETRO_CALLCONV *retro_set_image_index_t)(unsigned index);
1809 
1810 /* Gets total number of images which are available to use. */
1811 typedef unsigned (RETRO_CALLCONV *retro_get_num_images_t)(void);
1812 
1813 struct retro_game_info;
1814 
1815 /* Replaces the disk image associated with index.
1816  * Arguments to pass in info have same requirements as retro_load_game().
1817  * Virtual disk tray must be ejected when calling this.
1818  *
1819  * Replacing a disk image with info = NULL will remove the disk image
1820  * from the internal list.
1821  * As a result, calls to get_image_index() can change.
1822  *
1823  * E.g. replace_image_index(1, NULL), and previous get_image_index()
1824  * returned 4 before.
1825  * Index 1 will be removed, and the new index is 3.
1826  */
1827 typedef bool (RETRO_CALLCONV *retro_replace_image_index_t)(unsigned index,
1828       const struct retro_game_info *info);
1829 
1830 /* Adds a new valid index (get_num_images()) to the internal disk list.
1831  * This will increment subsequent return values from get_num_images() by 1.
1832  * This image index cannot be used until a disk image has been set
1833  * with replace_image_index. */
1834 typedef bool (RETRO_CALLCONV *retro_add_image_index_t)(void);
1835 
1836 struct retro_disk_control_callback
1837 {
1838    retro_set_eject_state_t set_eject_state;
1839    retro_get_eject_state_t get_eject_state;
1840 
1841    retro_get_image_index_t get_image_index;
1842    retro_set_image_index_t set_image_index;
1843    retro_get_num_images_t  get_num_images;
1844 
1845    retro_replace_image_index_t replace_image_index;
1846    retro_add_image_index_t add_image_index;
1847 };
1848 
1849 enum retro_pixel_format
1850 {
1851    /* 0RGB1555, native endian.
1852     * 0 bit must be set to 0.
1853     * This pixel format is default for compatibility concerns only.
1854     * If a 15/16-bit pixel format is desired, consider using RGB565. */
1855    RETRO_PIXEL_FORMAT_0RGB1555 = 0,
1856 
1857    /* XRGB8888, native endian.
1858     * X bits are ignored. */
1859    RETRO_PIXEL_FORMAT_XRGB8888 = 1,
1860 
1861    /* RGB565, native endian.
1862     * This pixel format is the recommended format to use if a 15/16-bit
1863     * format is desired as it is the pixel format that is typically
1864     * available on a wide range of low-power devices.
1865     *
1866     * It is also natively supported in APIs like OpenGL ES. */
1867    RETRO_PIXEL_FORMAT_RGB565   = 2,
1868 
1869    /* Ensure sizeof() == sizeof(int). */
1870    RETRO_PIXEL_FORMAT_UNKNOWN  = INT_MAX
1871 };
1872 
1873 struct retro_message
1874 {
1875    const char *msg;        /* Message to be displayed. */
1876    unsigned    frames;     /* Duration in frames of message. */
1877 };
1878 
1879 /* Describes how the libretro implementation maps a libretro input bind
1880  * to its internal input system through a human readable string.
1881  * This string can be used to better let a user configure input. */
1882 struct retro_input_descriptor
1883 {
1884    /* Associates given parameters with a description. */
1885    unsigned port;
1886    unsigned device;
1887    unsigned index;
1888    unsigned id;
1889 
1890    /* Human readable description for parameters.
1891     * The pointer must remain valid until
1892     * retro_unload_game() is called. */
1893    const char *description;
1894 };
1895 
1896 struct retro_system_info
1897 {
1898    /* All pointers are owned by libretro implementation, and pointers must
1899     * remain valid until retro_deinit() is called. */
1900 
1901    const char *library_name;      /* Descriptive name of library. Should not
1902                                    * contain any version numbers, etc. */
1903    const char *library_version;   /* Descriptive version of core. */
1904 
1905    const char *valid_extensions;  /* A string listing probably content
1906                                    * extensions the core will be able to
1907                                    * load, separated with pipe.
1908                                    * I.e. "bin|rom|iso".
1909                                    * Typically used for a GUI to filter
1910                                    * out extensions. */
1911 
1912    /* If true, retro_load_game() is guaranteed to provide a valid pathname
1913     * in retro_game_info::path.
1914     * ::data and ::size are both invalid.
1915     *
1916     * If false, ::data and ::size are guaranteed to be valid, but ::path
1917     * might not be valid.
1918     *
1919     * This is typically set to true for libretro implementations that must
1920     * load from file.
1921     * Implementations should strive for setting this to false, as it allows
1922     * the frontend to perform patching, etc. */
1923    bool        need_fullpath;
1924 
1925    /* If true, the frontend is not allowed to extract any archives before
1926     * loading the real content.
1927     * Necessary for certain libretro implementations that load games
1928     * from zipped archives. */
1929    bool        block_extract;
1930 };
1931 
1932 struct retro_game_geometry
1933 {
1934    unsigned base_width;    /* Nominal video width of game. */
1935    unsigned base_height;   /* Nominal video height of game. */
1936    unsigned max_width;     /* Maximum possible width of game. */
1937    unsigned max_height;    /* Maximum possible height of game. */
1938 
1939    float    aspect_ratio;  /* Nominal aspect ratio of game. If
1940                             * aspect_ratio is <= 0.0, an aspect ratio
1941                             * of base_width / base_height is assumed.
1942                             * A frontend could override this setting,
1943                             * if desired. */
1944 };
1945 
1946 struct retro_system_timing
1947 {
1948    double fps;             /* FPS of video content. */
1949    double sample_rate;     /* Sampling rate of audio. */
1950 };
1951 
1952 struct retro_system_av_info
1953 {
1954    struct retro_game_geometry geometry;
1955    struct retro_system_timing timing;
1956 };
1957 
1958 struct retro_variable
1959 {
1960    /* Variable to query in RETRO_ENVIRONMENT_GET_VARIABLE.
1961     * If NULL, obtains the complete environment string if more
1962     * complex parsing is necessary.
1963     * The environment string is formatted as key-value pairs
1964     * delimited by semicolons as so:
1965     * "key1=value1;key2=value2;..."
1966     */
1967    const char *key;
1968 
1969    /* Value to be obtained. If key does not exist, it is set to NULL. */
1970    const char *value;
1971 };
1972 
1973 struct retro_game_info
1974 {
1975    const char *path;       /* Path to game, UTF-8 encoded.
1976                             * Usually used as a reference.
1977                             * May be NULL if rom was loaded from stdin
1978                             * or similar.
1979                             * retro_system_info::need_fullpath guaranteed
1980                             * that this path is valid. */
1981    const void *data;       /* Memory buffer of loaded game. Will be NULL
1982                             * if need_fullpath was set. */
1983    size_t      size;       /* Size of memory buffer. */
1984    const char *meta;       /* String of implementation specific meta-data. */
1985 };
1986 
1987 #define RETRO_MEMORY_ACCESS_WRITE (1 << 0)
1988    /* The core will write to the buffer provided by retro_framebuffer::data. */
1989 #define RETRO_MEMORY_ACCESS_READ (1 << 1)
1990    /* The core will read from retro_framebuffer::data. */
1991 #define RETRO_MEMORY_TYPE_CACHED (1 << 0)
1992    /* The memory in data is cached.
1993     * If not cached, random writes and/or reading from the buffer is expected to be very slow. */
1994 struct retro_framebuffer
1995 {
1996    void *data;                      /* The framebuffer which the core can render into.
1997                                        Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER.
1998                                        The initial contents of data are unspecified. */
1999    unsigned width;                  /* The framebuffer width used by the core. Set by core. */
2000    unsigned height;                 /* The framebuffer height used by the core. Set by core. */
2001    size_t pitch;                    /* The number of bytes between the beginning of a scanline,
2002                                        and beginning of the next scanline.
2003                                        Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2004    enum retro_pixel_format format;  /* The pixel format the core must use to render into data.
2005                                        This format could differ from the format used in
2006                                        SET_PIXEL_FORMAT.
2007                                        Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2008 
2009    unsigned access_flags;           /* How the core will access the memory in the framebuffer.
2010                                        RETRO_MEMORY_ACCESS_* flags.
2011                                        Set by core. */
2012    unsigned memory_flags;           /* Flags telling core how the memory has been mapped.
2013                                        RETRO_MEMORY_TYPE_* flags.
2014                                        Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2015 };
2016 
2017 /* Callbacks */
2018 
2019 /* Environment callback. Gives implementations a way of performing
2020  * uncommon tasks. Extensible. */
2021 typedef bool (RETRO_CALLCONV *retro_environment_t)(unsigned cmd, void *data);
2022 
2023 /* Render a frame. Pixel format is 15-bit 0RGB1555 native endian
2024  * unless changed (see RETRO_ENVIRONMENT_SET_PIXEL_FORMAT).
2025  *
2026  * Width and height specify dimensions of buffer.
2027  * Pitch specifices length in bytes between two lines in buffer.
2028  *
2029  * For performance reasons, it is highly recommended to have a frame
2030  * that is packed in memory, i.e. pitch == width * byte_per_pixel.
2031  * Certain graphic APIs, such as OpenGL ES, do not like textures
2032  * that are not packed in memory.
2033  */
2034 typedef void (RETRO_CALLCONV *retro_video_refresh_t)(const void *data, unsigned width,
2035       unsigned height, size_t pitch);
2036 
2037 /* Renders a single audio frame. Should only be used if implementation
2038  * generates a single sample at a time.
2039  * Format is signed 16-bit native endian.
2040  */
2041 typedef void (RETRO_CALLCONV *retro_audio_sample_t)(int16_t left, int16_t right);
2042 
2043 /* Renders multiple audio frames in one go.
2044  *
2045  * One frame is defined as a sample of left and right channels, interleaved.
2046  * I.e. int16_t buf[4] = { l, r, l, r }; would be 2 frames.
2047  * Only one of the audio callbacks must ever be used.
2048  */
2049 typedef size_t (RETRO_CALLCONV *retro_audio_sample_batch_t)(const int16_t *data,
2050       size_t frames);
2051 
2052 /* Polls input. */
2053 typedef void (RETRO_CALLCONV *retro_input_poll_t)(void);
2054 
2055 /* Queries for input for player 'port'. device will be masked with
2056  * RETRO_DEVICE_MASK.
2057  *
2058  * Specialization of devices such as RETRO_DEVICE_JOYPAD_MULTITAP that
2059  * have been set with retro_set_controller_port_device()
2060  * will still use the higher level RETRO_DEVICE_JOYPAD to request input.
2061  */
2062 typedef int16_t (RETRO_CALLCONV *retro_input_state_t)(unsigned port, unsigned device,
2063       unsigned index, unsigned id);
2064 
2065 /* Sets callbacks. retro_set_environment() is guaranteed to be called
2066  * before retro_init().
2067  *
2068  * The rest of the set_* functions are guaranteed to have been called
2069  * before the first call to retro_run() is made. */
2070 RETRO_API void retro_set_environment(retro_environment_t);
2071 RETRO_API void retro_set_video_refresh(retro_video_refresh_t);
2072 RETRO_API void retro_set_audio_sample(retro_audio_sample_t);
2073 RETRO_API void retro_set_audio_sample_batch(retro_audio_sample_batch_t);
2074 RETRO_API void retro_set_input_poll(retro_input_poll_t);
2075 RETRO_API void retro_set_input_state(retro_input_state_t);
2076 
2077 /* Library global initialization/deinitialization. */
2078 RETRO_API void retro_init(void);
2079 RETRO_API void retro_deinit(void);
2080 
2081 /* Must return RETRO_API_VERSION. Used to validate ABI compatibility
2082  * when the API is revised. */
2083 RETRO_API unsigned retro_api_version(void);
2084 
2085 /* Gets statically known system info. Pointers provided in *info
2086  * must be statically allocated.
2087  * Can be called at any time, even before retro_init(). */
2088 RETRO_API void retro_get_system_info(struct retro_system_info *info);
2089 
2090 /* Gets information about system audio/video timings and geometry.
2091  * Can be called only after retro_load_game() has successfully completed.
2092  * NOTE: The implementation of this function might not initialize every
2093  * variable if needed.
2094  * E.g. geom.aspect_ratio might not be initialized if core doesn't
2095  * desire a particular aspect ratio. */
2096 RETRO_API void retro_get_system_av_info(struct retro_system_av_info *info);
2097 
2098 /* Sets device to be used for player 'port'.
2099  * By default, RETRO_DEVICE_JOYPAD is assumed to be plugged into all
2100  * available ports.
2101  * Setting a particular device type is not a guarantee that libretro cores
2102  * will only poll input based on that particular device type. It is only a
2103  * hint to the libretro core when a core cannot automatically detect the
2104  * appropriate input device type on its own. It is also relevant when a
2105  * core can change its behavior depending on device type. */
2106 RETRO_API void retro_set_controller_port_device(unsigned port, unsigned device);
2107 
2108 /* Resets the current game. */
2109 RETRO_API void retro_reset(void);
2110 
2111 /* Runs the game for one video frame.
2112  * During retro_run(), input_poll callback must be called at least once.
2113  *
2114  * If a frame is not rendered for reasons where a game "dropped" a frame,
2115  * this still counts as a frame, and retro_run() should explicitly dupe
2116  * a frame if GET_CAN_DUPE returns true.
2117  * In this case, the video callback can take a NULL argument for data.
2118  */
2119 RETRO_API void retro_run(void);
2120 
2121 /* Returns the amount of data the implementation requires to serialize
2122  * internal state (save states).
2123  * Between calls to retro_load_game() and retro_unload_game(), the
2124  * returned size is never allowed to be larger than a previous returned
2125  * value, to ensure that the frontend can allocate a save state buffer once.
2126  */
2127 RETRO_API size_t retro_serialize_size(void);
2128 
2129 /* Serializes internal state. If failed, or size is lower than
2130  * retro_serialize_size(), it should return false, true otherwise. */
2131 RETRO_API bool retro_serialize(void *data, size_t size);
2132 RETRO_API bool retro_unserialize(const void *data, size_t size);
2133 
2134 RETRO_API void retro_cheat_reset(void);
2135 RETRO_API void retro_cheat_set(unsigned index, bool enabled, const char *code);
2136 
2137 /* Loads a game. */
2138 RETRO_API bool retro_load_game(const struct retro_game_info *game);
2139 
2140 /* Loads a "special" kind of game. Should not be used,
2141  * except in extreme cases. */
2142 RETRO_API bool retro_load_game_special(
2143   unsigned game_type,
2144   const struct retro_game_info *info, size_t num_info
2145 );
2146 
2147 /* Unloads a currently loaded game. */
2148 RETRO_API void retro_unload_game(void);
2149 
2150 /* Gets region of game. */
2151 RETRO_API unsigned retro_get_region(void);
2152 
2153 /* Gets region of memory. */
2154 RETRO_API void *retro_get_memory_data(unsigned id);
2155 RETRO_API size_t retro_get_memory_size(unsigned id);
2156 
2157 #ifdef __cplusplus
2158 }
2159 #endif
2160 
2161 #endif
2162